Offshore drilling platforms are generally supported by towers constructed of prefabricated secured together. The offshore drilling platform support structure generally comprises a base section which is anchored by pilings to the ocean floor. It is often necessary to sequentially secure prefabricated sections together below the surface of water for assemblying the platform support structure at the offshore drilling site.
A typical support structure has a plurality of main leg sections comprising pipe having an inside diameter of six to seven feet and each prefabricated section of the structure may weigh for example, three million pounds.
Typical connectors heretofore devised for securing tubular members together are disclosed in the following U.S. Pat. Nos. 3,251,611; 3,273,915; 3,353,847; 3,427,048; 3,485,051; 3,929,355; and 4,026,227. Such devices have generally required extremely accurate and consequently expensive machining operations for forming mating sections in the coupling apparatus. In addition, such structures have required precise positioning of the sections of the coupling in relation to each other for securing sections of the connectors together. Further, such devices are generally suitable for connecting a single piece of tubing to another single piece of tubing. The devices are not particularly adapted to making a plurality of connections between ends of members which may or may not lie in a common plane.
In view of the massive size and weight of prefabricated sections of offshore drilling platform support structure which must supported by floating ships or barges while being lowered into position several hundred feet below the water surface, the assembly of an offshore drilling platform support structure has, heretofore, been very expensive and time consuming. Connectors of the type disclosed in the patents referred to above have not been particularly suited for platform assembly.